[Mechanism of reversibility of colchicine mitosis induced by colcemid]

Restoration of the normal mitosis after its block by colchicine was due to the additional protein synthesis (reformation of the spindle microtubules). Studies of reversibility of the statmokinetic reaction induced by colcemid showed the block of the protein synthesis by puromycin to have no influence on the rate of restoration of the normal mitotic regimen, but copper ions delayed this process. On the basis of these results it is considered that restoration of the K-mitosis induced by colcemid was mainly due to the tubule reassembly. Probably the prevalence of the processes of reformation and reassembly of microtubules during the restoration depended on the extent of their destruction and the pattern of binding by the damaging agent of the tubular protein pool subunits.